Rolled eraser and holder



July 19, 1966 KWONG Ll LOU ROLLED ERASER AND HOLDER Filed Feb. 15, 1965 [LI www wmlm INVENTOR. 40W 11 [01/ #rmewnf United States Patent 3,261,325 ROLLED ERASER AND HOLDER Kwong Li Lon, Civil Air Transport Inspection Dept, Tainan Air Field, Tainan, Taiwan, China Filed Feb. 15, 1965, Ser. No. 432,727 16 Claims. (Cl. 126-36) This invention relates to erasers, and has particular reference to an eraser rolled in helical form and disposed in a holder, so as to form an eraser strip which emerges trom the bottom of the holder.

An eraser assembly, according to the preferred embodiment of my present invention, utilizes:

(1) an eraser in helical form, so as to produce a sharp edge along the length of the eraser, as a sharp surface is more efficient than a flat surface in erasing small areas;

(2) a novel holder tor such eraser, having an upper member in cylindrical form for enclosing the helical eraser and a hinged lower member with a conical outlet portion for the eraser strip;

(3) means for permitting relative rotation between the upper and lower members to force the eraser through the outlet portion, in which, preferably, the cylindrical member is pivotally connected to a ring by means of a hinge assembly, and the conical member is connected therebetween, so that the cylindrical and conical members of the holder are relatively rotatable and can be opened to refill the device;

(4) an axle and spring assembly in the tube member for guiding and urging the eraser toward the conical member; and

(5) means for preventing the eraser strip from retracting into the cylindrical member during erasing.

One embodiment of my present invention provides, in a novel holder (for enclosing and guiding a helical eraser, a top end adapted for installation in a power driving rotary implement, which may be driven by external or internal electrical power, pneumatic power, spring means or the like, so as to constitute a power-driven eraser.

Another embodiment of my present invention provides, in a novel holder for enclosing and guiding a helical eraser, an axial bore formed in one end thereof so as to be adapted to be mounted on a pencil, together with means for securing this holder to the inserted pencil.

For the purpose of illustration, there is shown a preferred embodiment of the invention in the accompanying drawing, in which FIGURE 1 is a front elevation of an eraser holder, according to the present invention, but without an eraser installed inside;

FIGURE 2 is an elevation of an eraser holder, taken along lines 22 of FIGURE 1, but showing an eraser extending out of the holder;

FIGURE 3, parts (a) and (b) taken together, is an elevation showing the eraser holder in its opened condition and a helical eraser outside thereof and disposed for insertion therein;

FIGURE 4 is a view, in section, taken along lines 4-4 of FIGURE 1;

FIGURE 5 is a view, in section, taken along lines 55 of FIGURE 2;

FIGURE 6 is an enlarged sectional view, taken along lines 66 of FIGURE 3;

FIGURE 7 is a view, in section, taken along lines 77 of FIGURE 4;

FIGURE 8 is a view, in section, taken along lines 88 of FIGURE 4;

FIGURE 9 is a sectional view, similar to FIGURE 5, but showing as an alternate embodiment of holder in which the top end has an axial bore adapted to receive and hold a pencil; and

"ice

FIGURE 10 is a view, in section, taken along lines 1010 of FIGURE 9.

Referring now to the drawing, an eraser assembly according to my present invention includes a cylindrical member 11 and a conical member 12. A series of gear teeth are (formed in the outer periphery of the conical member 12 adjacent to the cylindrical member 11, thus providing a toothed flange 13.

Beneath the toothed flange 13, a ring 14 is pivotally linked to the cylindrical member 11 at the toothed flange 13 by a hinge assembly 15. The conical portion 12 extends through the ring 14. Opposite side of the hinge assembly 15, a spring clip assembly 16 passes over the toothed flange 13 of the conical member 12 and releasably engages the ring 14, as shown in the FIGURES l, 3 and 5, so as to hold the conical member 12 in place. The clip assembly 16 preferably terminates in a small ball and is connected to the cylindrical member 11 by a strip spring 16A. The clip assembly 16 is so positioned as to normally incline inwardly and slide over the toothed flange 13 to engage the under side of the ring 14. The clip assembly is released by manually pushing outwardly thereon.

Two rods 17, which may be any appropriate configuration, are pivotally connected to the cylindrical member 11 at opposite sides thereof by two pins 18. Two slots 19 formed in the cylindrical member 11 (see FIGURE 7) permits the rods to be pivoted into the inside of the cylindrical member 11. The rods 17 and slots 19 are oppositely disposed, and the slots 19 do not extend the entire whole length of the cylindrical member 11. Adjacent the pivoted ends of rods 17, two small stop bars 20 are provided on the cylindrical member 11, so as to prevent the rods 17 from pivoting outwardly.

Two pawls 21 engage the toothed flange 13 and are held in position by two strip springs 22 fastened at the lower outboard portions of the rods 17. Each strip spring 22 is disposed within a U-shaped fulcrum 23, which is fastened to the lower portion of cylindrical member 11, as shown in FIGURES l, 2, 3, 4 and 7. The pawls 21, springs 22 and fulcrums 23 are so positioned that the pawls normally engage the toothed flange 13. When the two rods 17 are moved inwardly into the tube member 11 through slots 19 by manual pressure, the strip springs 22 are carried inwardly, pivoting about the fulcrums 23 to move the pawls 21 outwardly and disengage them from the toothed flange 13. When the manual pressure is released, the pawls re-engage the toothed flange to lock and hold the relative rotary disposition of the cylindrical member 11 and conical member 12.

If the holder is to be used for manual erasing purposes only, the pawls 21, the strip springs 22, the fulcrums 23, and the teeth on the toothed flange 13 may be eliminated if desired, since the erasing motion will be primarily linear. high speed rotation is utilized, these components function to prevent the cylindrical member 11 and conical member 12 from rotating relative to each other during erasing.

The cylindrical member 11 has an axle 24 on which a coil spring 25 and a circular plate 26 are slidably disposed. The lower end of the axle 24 has a small butt or cup portion of somewhat larger diameter than that of the bore of the circular plate 26, so that the circular plate 26 is prevented from sliding off of the axle 24 in response to the urging of the coil spring 25, when the holder is in its opened condition A short stud 27, formed in the center of the toothed flange 13 (see FIGURES 3, 4 and 5), guides and mates with the butt or cap of the axle 24. An outlet aperture at one side of the toothed flange 13 opens into an outlet tube 28 to receive the eraser material and pass it In power driven applications, where through the conical member 13 A curved guide plate 29 is disposed adjacent the outlet aperture and has a sharp leading edge for separting a rolled eraser 30 into an eraser strip, as is best shown in FIGURE 6.

The rolled eraser 30, according to the invention (see FIGURES 3, 5 and 9), is in helical configuration. The eraser unrolls to form a strip which is preferably of square cross section, in order to provide more angular portions for erasing small areas. The eraser is installed in the cylindrical member 11 along the axle 24, so as to abut the circular plate 26. The spring force of coil spring 25, when the eraser holder is in the closed condition, presses the circular plate 26 against the eraser 30 and its bottom is then urged against the curved guide plate 29 on the conical member 12.

The eraser 30 may be formed as either a clockwise or counter-clockwise helix The direction, curvature and location of the curved guide plate 29 with respect to the outlet opening on the toothed flange 13 is, of course, determined by the direction of the helical cut of the rolled eraser 30, so as to be disposed such that the utmost lower eraser strip end will be separated by the curved guide plate 29, when the eraser is rotated. The eraser 30 is clamped in position by the rods 17 when the rods are pressed inwardly, and, at the clamped condition, eraser material is expelled from or retracted into the outlet tube 28, when the tube member 11 and the conical member 12 rotate relative to each other For a power driven eraser holder, which is provided with the pawls 21, strip springs 22 and fulcrums 23, the eraser 30 can be turned only when the rods 17 are depressed inwardly to disengage the pawls 21 from the toothed flange 13. Otherwise, the cylindrical member 11 and conical outlet member 12 are locked together and cannot rotate relative to each other Due to the curved guide plate 29 being set to one side on the top surface of the conical member 12, the depressed rods 17 encounter a dead position at each cycle of rotation when each of the rods reaches the curved guide plate 29, as is best shown in FIGURES 4 and 7, in which the dotted lines show the limit of inward movement of the rods 17. The rod adjacent the curved guide plate 29 has a small inward movement, while the opposite rod has a large inward movement The small inward movement, however, is enough to disengage the pawl 21 from the toothed flange 13, so as to permit the necessary relative movement between the cylindrical member 11 and conical member 12.

As has been explained, the eraser strip either will be turned into outlet tube 28 and will emerge from the conical outlet portion 12 when the tube member 11 and conical member 12 rotate relative to each other or the bottom eraser strip end 30A will be retracted from the outlet into the holder, depending upon the direction of relative rotation of the device and the direction of the helical cut of the eraser body 30.

In order to prevent the eraser strip 30A from being retracted during erasing, a securing means is provided which may take any appropriate configuration, for example, an actuator 31, shown as an equilateral triangular block, with rounded corners A shaft 32 passes through and is fixed on the actuator 31 at an off-center point; thus the actuator acts in an eccentric manner. By rotating the actuator 31 by means of the shaft 32, the actuator 31 rotates to squeeze a flexible side 28A of the outlet tube 28 against the eraser strip therewithin, so as to prevent retraction Rotation of the actuator 31 is controlled by means of an actuator knob 33, which is attached to the actuator shaft 32.

A top portion 11A of the tube member 11 may have different configurations for different purposes It may be the same size as cylinder, for manual erasing purpose only, and an attaching hook or clip may be installed thereon for attachment to a pocket. As shown in the drawings, cylindrical base 11A is adapted for insertion into a power driving unit for power driven erasing Alternatively, an axial bore 34, with bore forming wall 35, as is best shown in FIGURES 9 and 10, is adapted to have a pencil inserted therein so as to be convenient for use. Means for securing the inserted pencil are preferably provided, which may be, for example, a pair of convex springs 36 extending from the bore-forming wall, their inner ends free and outer ends secured thereon so as to clamp the inserted pencil In this embodiment, the holder may be further modified to have the coil spring 25 enclosed. This coil spring 25 is then large enough to slide along the bore wall 35 Grooves or convex configurations may be added on the conical outlet member 12 for convenience in actuating. The length of the tube member may be different for various purposes, for instance, it may be long for manual erasing, and short for power-driven erasing and for inserting on pencil Similarly, the diameter may vary.

As the eraser body 3% is turned toward outlet and is gradually used up, the coil spring 25 urges the remaining eraser material toward the outlet and against the curved guide plate 29 When the last eraser of the eraser body 39 reaches the curved guide plate 29, further relative rotation produces no additional eraser material. A new eraser body 30 must then be utilized as a refill. The process of refilling is: (1) Push the spring clip 16 outwardly, and pivotally open the cylindrical member 11; (2) Insert a new eraser body 30, whose bore is slightly larger than the butt or cap end of axle 24, on the axle 24 against the circular plate 26 and the urging of coil spring 25; (3) Pivotally return the cylindrical member 11 to the conical member 12; (4) Slide the clip 16 over the toothed flange 13 to the under side of ring 14. The old portion of eraser strip 30A remaining in the outlet tube 28 will be pushed to outside by the new eraser strip when the new eraser is fed int-o the outlet tube 28.

The invention claimed is:

1. An eraser device for operating rolled strip erasers, comprising:

an eraser holder having first and second members connected by linking means;

clip means for locking the first and second members in a closed position;

an eraser body of generally helical configuration disposed within the eraser holder;

an eraser strip outlet tube formed in the second member and having a curved guide member thereon, said tube receiving a strip of eras-er material from the helical eraser body;

means for urging the eraser body towards the outlet tube; and

means for selectively clamping the eraser body strip within the outlet tube.

2. The combination of claim 1, and in which:

the first member is generally cylindrical in configura tion; the second member is generally conical in configuration, and has an outwardly extending flange'adjacent the first member when in the closed position;

said linking means includes a hinge attached between a ring and the upper member at one side thereat, said ring enclosing the lower member and engaging said clip means;

said eraser clamping means releasably prevents eraser retraction during erasing and includes an actuator, and means for rotatably disposing the actuator in the lower member between the outlet tube and the wall thereof, including a rotatable shaft which passes therethrough and is attached eccentrically to said 3. The combination of claim 1, and in which said urging means including an axle, a coil spring and a circular plate disposed in sequence about said axle, and said eraser body is disposed in said holder between the plate and second member.

4. The combination of claim 1, and including a pair of slots formed in the first member and two rods pivotally attached to the first member so as to pass through said two slots to selectively clamp the eraser body against rotation when said first member and second member r0- tate relative to each other.

5. The combination of claim 4, and in which each of said rods has a stop associated therewith to prevent the outward pivoting of said rod.

6. The combination of claim 5, and in which the eraser holder has an axle, a coil spring and a circular plate disposed in sequence about said axle, and said eraser body is disposed in said holder between the plate and the lower member.

7. The combination of claim 6, and in which the end end of said axle, adjacent the lower portion, is slightly larger in diameter than a bore formed in said circular plate, and is slightly less in diameter than the inner dimension at said eraser body, so that said ax-le retains said circular plate, while the eraser body is insertable thereon.

8. The combination of claim 7, and in which each of said rods has a pawl attached thereto by a strip spring so as to engage an outward toothed flange on the second member, and including two fulcrums attached to the first member adjacent to the unpivoted end-s of said rods to support and guide said strip springs, so as inhibit relative rotation between the first and second members when the pawls engage the flange teeth and to permit such relative rotation when the rods are depressed inwardly to disengage the pawls from the flange teeth.

9. The combination of claim '1, and in which the top portion of said first member terminates in a boss for en gaging a rotary drive source.

10. The combination of claim 9, and in which the first member has a pair of slots formed therein, and two rods pivotally attached thereto so as to pass through said slots to selectively clamp the eraser body against rotation.

11. The combination of claim 10, and in which each of said rods has a stop associated therewith to prevent the outward pivoting of said rod.

12. The combination of claim 11, and in which each of said rods has a pawl attached thereto by a strip spring so as to engage an outward toothed flange on the second member, and including two fulcrums attached to the first member adjacent to the unpivoted ends of said rods to support and guide said strip springs, so as to inhibit relative rotation between the upper and lower members when the pawls engage the flange teeth and to permit such relative rotation when the rods are depressed inwardly to disengage the pawls from the flange teeth.

13. The combination of claim 1, and in which the top portion of the first member has a bore formed therein and including pencil holding means disposed in said bore.

14. The combination of claim 13, and in which the pencil holding means includes two convex strip springs attached to the bore wall at their outer ends and free at their inner ends, so as to exert two inward clamping pressures against an inserted pencil.

'15. The combination of claim 14, and in which the first member has a pair of slots formed therein, and two rodspivotally attached thereto so as to pass through said two slots selectively to clamp the eraser body against rotation.

16. The combination of claim 15, and in which each of said rods has a stop associated therewith to prevent theoutward pivoting of said rod.

References Cited by the Examiner UNITED STATES PATENTS 413,798 10/ 1889 Young 36 2,223,921 12/1940 Rudiger l2036 FOREIGN PATENTS 326,987 2/ 1954 Switzerland.

LAWRENCE CHARLES, Primary Examiner. 

1. AN ERASER DEVICE FOR OPERATING ROLLED STRIP ERASERS, COMPRISING: AN ERASER HOLDER HAVING FIRST AND SECOND MEMBERS CONNECTED BY LINKING MEANS; CLIP MEANS FOR LOCKING THE FIRST AND SECOND MEMBERS IN A CLOSED POSITION; AN ERASER BODY OF GENERALLY HELICAL CONFIGURATION DISPOSED WITHIN THE ERASER HOLDER; AN ERASER STRIP OUTLET TUBE FORMED IN THE SECOND MEMBER AND HAVING A CURVED GUIDE MEMBER THEREON, SAID TUBE RECEIVING A STRIP OF ERASER MATERIAL FROM THE HELICAL ERASER BODY; MEANS FOR URGING THE ERASER BODY TOWARDS THE OUTLET TUBE; AND MEANS FOR SELECTIVELY CLAMPING THE ERASER BODY STRIP WITHIN THE OUTLET TUBE. 